Color light signal



Oct. 1, 1929. I D. BROWN 1,730,316

COLOR LIGHT SIGNAL Filed March 15, 1926 a a. @311 MM flaw Patented Oct. 1, 19 29 UNITED STATES PATENT OFFICE PAUL D. BROWN, 01? NEW HAVEN, CONNECTICUT, ASSIGNOB 'IO GENERAL RAILWAY SIGNAL COMPANY, OF ROCHESTER, NEW YORK COLOR LIGHT SIGNAL Application filed March 15, 1926. Serial No. 94,729.

This invention relates to the casings or housings for color light signals.

The light projecting units of color light signals are, of course, enclosed and protected by a suitable casing or housing; and to give access to the light projecting unit, for the purposes of replacing lamps or changing lenses, it is common practice to provide the casing with a swinging door, or detachable back. It will be evident that when the door, detachable panel or the like, of the casing of the light projecting unit is opened, light from exterior sources, such as sunlight, may be projected through the signal and give it the appearance of being lighted. Such an artificial indication may be more favorable than the existing trailic conditions justify, and may easily mislead the engineman of an approaching train.

As a solution to this problem, it has been proposed to use a common door or panel for all of the light projecting units, so that if the sun is shining through the signal, all of the indications, such as green, yellow and red, will be given simultaneously, thereby giving an indication which can not be accepted by the engineer as a favorable indication. For various reasons, however, it is desirable to use a unit construction of the light projecting units, with individual casings and individual doors; and the present invention relates more particularly to the provision of simple and efficient means for compelling the individual doors of the light projecting units to be opened in such a way that a misleading and favorable indication can not be given by light from external sources.

Various other specific objects, purposes and advantages of the invention will be in part apparent, and in part pointed out as the description progresses.

In the accompanying drawings, Fig. 1 illustrates a side elevation of the unit light signal, with individual doors, together with the means constituting the present invention; and Fig. 2 shows a rear elevation of the signal constructed in accordance with the present invention.

While the means of this invention may be applied to the casings of various types of color light signals, I have illustrated the invention applied to a unit light signal of the well known type, shown and described, for example, in the application of S. M. Day, Serial No. 508,19 l, filed October 17, 1921. This signal comprises a plurality of individual or unit box-like casings, three being shown, super-imposed and fastened together, and suitably supported on a bracket or pole. Each casing includes a light source, lenses or equivalent light concentrating and dispersing instrumentalities; but since the particular construction of the light projecting unit itself forms no part of the present invention, no attempt has been made to illustrate any particular form. It should be understood that these light projecting units give difierent color indications, such as green, yellow and red; and it is assumed that the topmost unit will give a green indication, the middle unit a yellow and the lower one a red.

Each of these unit casings is provided with a rear door I) supported on suitable hinges 1 at the side, and provided with a suitable hasp fastener 2. As shown, each door is also provided with a ventilator 3.

At the free side of the door D of the lower casing, near the upper edge, is a member or lug L, integral with the door or suitably fastened thereto, which projects upwardly and overlaps the lower edge of the door for the middle casing, so that the middle door can not be swung back to the open position, without carrying with it the lower door. The door for the middle casing is provided with the same kind of a lug L, disposed in the same way, and acting to prevent the door for the upper casing being'swung, without opening the door for the middle casing.

lit will be observed that the lower door may be opened alone, but that the middle door can not be opened without also opening the lower door, and that the upper door can not be opened without also opening both the middle and lower doors. If the lower door is open, and the sun should shine through, a red or stop indication is given. If the middle door is open, the lower door must also be open, so that the sun shining through gives a red as well as a yellow indication. Similarly, a

sarily exposing all of the others to smoke,-

dirt and the like.

The particular location and disposition of the projecting members or lugs L. shown is predicated on the assumption that the indications of the signal are green, yellow and red, starting from the top; but it will be evident that other arrangements of colors or indications may be employed, and the same expedient applied by arranging the lugs on the right door and on the upper or lower edge, as required, to prevent the door oi any light unit glvmg one lndication being open unless the door or doors giving a more rest-rictive indication are also open.

While the idea of means underlying the invention has been disclosed in a very simple form, various other constructions and arrangements of parts may be employed to ob tain the same functions and advantages; and I desire to have it understood that the invention;is not limited to the particular construc tion. shown and described, but is susceptible ofconsiderable modification and adaptation in practice.

What I claim is 1. In a color light signal, in combination, a plurality of light projecting units giving color. indications of different.restrictiveness, each unit having a, casing, a light concentrating means in the casing and an opposed movable door giving access to the interior of the casing, and means preventing'movement of the door of each casing unless the doors of all the units giving a more restrictive indication are also moved.

2. In a light signal, the combination with aplurality. of. casings each having a light projecting unit giving indications of different restrictiveness and each having a swinging door opposite the said unit, of. means cooperating w1th said doors to prevent swinging open of the door of a casmg unless the doors of all the other casings of the units giving amore restrictive indication are also swung to a corresponding open position.

3. A color light signal comprising a plurality of unit casings super-imposed and each including a light projecting unit giving a being supported to swing on a common axis and members associated with said doors and extending into the pathof movement of ad jacent doors, whereby the door of a casing can not be swung open unless the doors of all casings giving a more restrictive indication are swung open to a corresponding extent.

4. A color light signal comprising two casings one above another, a light projecting unit in each casing, giving distinctive indications of different restrictiveness, a movable door for each casing opposite the said unit, and a member associated with the door of the casing giving a more restrictive indication and cooperating with the other door for preventing movement of the door of the casing giving the more favorable indication unless the door of the casing giving a more restrictive indication is also moved.

5. A. light signal. comprising a plurality of casings, a light projecting unit in each casing g a distinctive indication of different restrictiveness from the others, doors opposite the said units afiording access to said units, and means associated with said doors for requiring said doors to be opened in a sequence which exposes with each light projecting unit other than the most restrictive, all other light projecting units giving more restrica tive indications.

6. A light signal comprising, a plurality of identical, matching, unit casings, each casing having a light projecting means giving a distinctive indication of different restrictiveness from the others and a door opposite said means openable to give access to said means, and a lug on each door except that of the casing giving theleast restrictive indication, extending when such door is closed into-the path of opening movement of the door of the casin giving the next less restrictive indication, whereby to avoid dangerous phantom indications while the signalis being inspected, repaired, and the like.

In testimony whereof I affix my signature.

PAUL D. BROWN. 

